Printing stuff and printing method



Patented Sept. 30, 1930 UNITED STATES PATENT OFFICE ERNST BURI, or ZURICH, SWITZERLAND rRinTrnG STUFF AND PRINTING METHOD No Drawing. Applicationfiled May 25, 1927, Serial No. 194,241, and. in Germany May 25, 1926.

My invention relates to a dusting powder adapted to be reprinted; that is to say, a dusting powder having the quality of producing a printing Surface by being transferred to a lithographic stone, metal plate or the like. According to my invention the dusting powder contains lycopodium impregnated with soap. 4

The preparation of this dusting powder may be performed in the following manner: 5 parts soap powder are added to 100 parts lycopodium moistened in water. The mixture obtained in this manner is well dried on a stove.

' The preparation of a printing surface with the dried dusting powder obtained in this manner may be performed as follows A paper having a surface of a swelling layer, for example gelatine, gum, glue or casein, is sub- 1 jected fora period of l 2 minutes to lukewarm water. As a suitable paper for instance Autotype Co. London, double transfer paper may be employed. The paper will then be dried with a blotting-paper or handkerchief q? and then the above described dusting powder is equally distributed on the paper by means of cottonwool. The powder containing lycopodium impregnated with soap has the quality of being capable of equal distribution on the swelling layer. The dusted paper is sensitized in a solution of 24:% kaliurnbiohromate- (potassium) then after being 7 dried it is exposed for a period of 5-10 minin sharp outline. The paper is then subjected utes under a negative until the copy is visible to the action of warm water so as to cause it to swell and then sprayed under strong water pressure, so that those parts not actedonby the light are washed away and a clear image able printing surface and passed through alithographic or other suitable'printing press. By this means a fatty impression or copy of will appear. The paper is dried and then laid pregnated powder may be incorporatedin' an emulsion containing gelatine or other suitable substances, and this weakemulsion'poured upon a suitable paper surface by machine in such manner that the impregnated lycopodium swims at the'top of the surface, the layer being then dried. From this point, the paper is treated in the same manner as described above; that IS to say, it is sensitized, exposed" and so on. The paperso manufactured may be produced in any desired length.

7 What I claim is:-

A dusting powder adapted to be reprinted containing lycopodijum impregnated with soap. 7 I

In testimony whereof 'I havesigned my name to this specification.

' ERNST BURI.

Uthe impregnated lycopodium is obtained for instance on the stone, which willrbe treated in the usual manner; that is to'say, the fatty impression will be treated with gum, caustic 

